Yes, the hose goes to the large intake hose that connects to the throttle body. There are two hoses that connect there, one for the IAC, the other for the PCV. Its a moulded hose. If its not connected there, I would be surprised if it ran very well as you would have a massive leak bypassing the AMM.

Also, get rid of AC, it's a pain in the ass an you don't need it in dry heat like you have in PDX. Roll the window down in August, less stuff to go wrong. Get an A or B cam in there and you'll enjoy the smooth rev to 5k now and then. Makes the car pretty fun without having to redline it.

Also if you aren't keen on wiring too much you can convert to Breakerless ignition from a 75-80 model, simple and bombproof. If you can find a 1989 model you can pull the EZK computer ignition system. It's the best for these cars.

Volvo made two different dash styles in the 240's. Early cars didn't get the extra guage spots like yours did. RWC listed the years for the early dash. That cluster added other guages that weren't available otherwise. The other spot to install guages in the early dash was to drill out holes in the actual dash and install there.

The board functions to reduce warranty (ha!) service by classifying varying temperatures, as sensed by the thermistor in the head, into three ranges of the gauge. It turns the gauge into an idiot light with roughly four states: cold, cool, normal, and hot.

M47 is susposed to use the Type F ATF but you can put anything in it, some people put the redline in it or other thicker oil, it just takes a wee bit longer to warm up and the shifts can be a little slower to do before warmed up with thicker oil. Main thing is make sure it's in a gear or the next right gear before you stomp on it.

Third gear is the weak gear. I replaced 4 manual m46's in one year once in a turbo 740 wagon. One time downshifting into third on Cornholiness pass back when they still let you pass on that road, shifted into third, stomped on it, zing, nothing. Gears stripped, slapped it back into 4th, kept going.